Dual nature of radiation and matter practice · Mixed difficulty

A particle with rest mass zero is moving speed $c$. The de-Broglie wavelength associated with it

An $\alpha \mathrm{ - Particle}$ and a deuteron are moving with velocities v and 2v respectively. What will be the ratio of their de Broglie wavelengths-?

A metal plate gets heated when cathode rays strike against it due to

The energy of a photon is $E = hv$ and the momentum of photon $p = \frac{h}{\lambda },$ then the velocity of photon will be

Millikan’s oil-drop experiment established that

The difference between kinetic energies of photoelectrons emitted from a surface by light of wavelength 2500$\mathop A\limits^ \circ$ and 5000$\mathop A\limits^ \circ$ will be

Which one of the following statements regarding photo-emission of electrons is correct?

Which of the following is not the property of a cathode ray

Assertion: The momentum of a photon is equal to $\mathrm{p}=\mathrm{h} / \lambda$.

Reason: According to Planck $\mathrm{E}=\mathrm{hv}$

According to Einstein $\mathrm{E}=\mathrm{mc}^2$.

So that $\mathrm{mc}^2=\mathrm{hv} \Rightarrow \mathrm{p}=\mathrm{mc}=\mathrm{h} / \lambda$

Two electrons are moving with non-relativistic speeds perpendicular to each other. If corresponding de Broglie wavelengths are $\lambda_1$ and $\lambda_2$ their de Broglie wavelength in the frame of reference attached to their centre of mass is :

The slope of frequency of incident light and stopping potential graph for a given surface will be

A 5 W source emits monochromatic light of wavelength $5000\mathop A\limits^ \circ$. When placed 0.5 m away, it liberates photoelectrons from a photosensitive metallic surface. When the source is moved to a distance of 1.0m, the number of photoelectrons liberated will be reduced by a factor of

In Millikan’s oil drop experiment, a charged drop of mass $1.8 \times {10^{ - 14}}$ kg is stationary between the plates. The distance between the plates 0.9 cm and potential difference between the plates is 2000 V. The number of electrons on the oil drop is

The time taken by a photoelectron to come out after the photon strikes is approximately

A beam of light of wavelength $\lambda$ and with illumination $L$ falls on a clean surface of sodium. If $N$ photoelectrons are emitted each with kinetic energy $E,$ then

Colour of star is an indication of its:-

Moving with the same velocity. Which of the following has the longest be Broglie wavelength

For a body moving with relativistic speed, if the velocity is doubled, then

If the frequency of light in a photoelectric
experiment is doubled, the stopping potential will:

The debroglie wavelength of an electron is $\lambda$ and has energy ${E}$. If the de Broglie wavelength is reduced by $25 \%$, then how much extra kinetic energy will the electron have now

The special theory of relativity is based on the frame of reference which has constant?

Ultraviolet radiation of 6.2eV falls on an aluminium surface (work function 4.2eV). The kinetic energy in joule of the fastest electron emitted is approximately

The colour of the positive column in a gas discharge tube depends on

Doubly ionised helium atom and hydrogen ions are accelerated, from rest, through the same potential difference. The ratio of final velocities of helium and hydrogen is

The de-Broglie wavelength is proportional to

In the photoeletric effect, electrons are emitted

Statement-1: If an electron has the same wavelength as a photon, they have the same energy.
Statement-2: By de-Broglie hypothesis, $p=h / \lambda$ for both the electron and the photon.

Planck’s constant has the dimensions of

If ${\mathrm{g}_E}$ and ${\mathrm{g}_M}$ are the acceleration due to gravity on the surfaces of the earth and the moon respectively and it Millikan’s oil drop experiment could be performed on the two surfaces, one will find the ratio $\frac{{\mathrm{electronic\;charge\;on\;the\;moon\;}}}{{\mathrm{electronic\;charge\;on\;the\;earth\;}}}$ to be

An electron is accelerated under a potential difference of 182 V. The maximum velocity of electron will be
(Charge of an electron is $1.6 \times {10^{ - 19}}$ C and its mass is $9.1 \times {10^{ - 31}}\;$ kg)